In a vehicle-mounted headlamp, the following configuration is known: when a lighting device for a light source is attached to an opening portion provided at the bottom of a headlamp case, such that the lighting device for a light source constitutes part of a wall portion of the headlamp case, the headlamp case and the lighting device for a light source are integrated to thus ensure a water proofing property in the headlamp.
As the lighting device for a light source employed in the headlamp thus constructed, there is the one in which an output connector to which an output harness for supplying power to a light source is connected is provided within a recessed portion at the top of a case of the lighting device for a light source (Patent document 1).